JP2591893Y2 - Pressure adjusting device for twin screw extruder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a pressure adjusting device for a twin-screw extruder.

(Prior Art) Conventional Example of FIGS. 8 to 12 (Japanese Patent Laid-Open No. 2-62222)
In the conventional twin screw extruder in which a barrel and a screw are combined, resin is sent from the screw elements 5 and 6 to the screw elements 7 and 8 via the seal rings 3 and 4. In FIG. 8, the seal ring is used.
The edge portions 11 and 12 of 3 and 4 are close to the edge portions 23 and 24 of the barrel 21, and the resin sent from the screw elements 5 and 6 has a small flow due to the small clearances 30 and 31. Squeezed. Therefore, the resin pressure on the screw elements 5 and 6 increases. Although the increase in pressure is not described in detail, it serves to increase the degree of kneading in the twin-screw extruder. FIG. 9 is a sectional view taken along the line DD in FIG.

Next, when the barrel 21 is slightly moved in the direction a as shown in FIG. 10 by moving means (not shown), the gap formed by the seal rings 3, 4 and the edge portions 23, 24 of the barrel 21 is denoted by reference numeral 40, As shown in 41, the gaps are larger than the gaps 30 and 31 before the movement. Accordingly, the resin pressure is reduced, and the kneading degree is reduced.

Next, when the barrel 21 is further moved in the direction b as shown in FIG. 11, the gap is further increased to become the maximum gap as shown by reference numerals 50 and 51, the resin pressure is further reduced, and the kneading degree is further reduced. That is, the flow of the resin is sealed by the seal rings 3 and 4, and the gap between the barrel 21 and the seal rings 3 and 4 is changed by changing the relative positions of the screw and the barrel in the axial direction. Is changed, and as a result, the resin pressure is adjusted. The screw may be moved in the axial direction to change the relative position between the sealing and the large-diameter barrel. Still other conventional examples are disclosed in JP-B-36-14119, JP-A-49-39657, and U.S. Pat. No. 3,382,536.

(Problems to be solved by the invention) In a twin-screw extruder, various pressure adjustment mechanisms in the middle of the screw have been conventionally devised, but they are not practical.

That is, in the one disclosed in the above-mentioned JP-A-2-62222,
No barrel movement mechanism is specified. In the case of the shape of the seal ring 4, the cross section shown in FIG. 9 was obtained, and the molten resin passage could not be made sufficiently small, so that the pressure adjusting function was incomplete.

Further, as shown in FIG. 13, the inner diameter of the drawing mechanism 60 is smaller than the outer diameter of the screw 61, so that the insertion and withdrawal work of the screw 61 is difficult, as shown in FIG. In addition, a sliding portion, for example, a throttle mechanism 60 and a container section 62
There is a drawback that the molten resin enters the gap and leaks. In addition, there is a problem that the resin that has entered deteriorates and solidifies, and the sliding member cannot move. In addition, 63 and 63 'are guide bolts, 64 is a machine frame, and 65 is a nut.

Next, the one disclosed in Japanese Patent Application Laid-Open No. 49-39657 has the same disadvantages as the conventional example shown in FIG. 13 because a part of the outer diameter of the screw 74 is larger than the inner diameter of the cylinder 75 as shown in FIG. At the same time, since the mechanism is complicated, there is a problem with difficulty in screw production. In FIG. 14, the cylinder 75 can move in the axial direction in the exterior 71 along the axis of the screw 74 together with the flapper port 76 to ensure the adjustment of the circular gap 78. For this purpose, an extension 79 of the cylinder 75 is provided with a thread 70, a nut which is rotated by the drive of the gear 72.
It is designed to interact with 80.

Also, as shown in the prior art U.S. Pat.No. 3,382,536, the screw is moved in the axial direction to change the performance of the extruder.However, the drive unit structure of the twin-screw extruder screw is complicated, The screw position could not be adjusted from outside.

The present invention provides a pressure adjusting device for a twin-screw extruder that can adjust the movement of a cylinder in an axial direction and can sufficiently increase the resin pressure in a screw. By providing a device that adjusts the movement of the cylinder between the drive reducers, the risk of leakage of raw material and resin is eliminated, and a reverse flight screw in which a reverse feed action occurs due to screw rotation in the pressure increasing section. In addition, the pressure can be reliably adjusted by combining a relief groove of the cylinder inner diameter.

(Means for Solving the Problems) For this reason, the present invention is a twin-screw extruder capable of inserting and removing a screw without disassembling the cylinder, and which rotates to move the cylinder position in the axial direction. A cylinder moving mechanism comprising an adjustment nut which cannot be moved in the direction and a screw portion of a cylinder for screwing the nut is provided between the raw material supply section and the screw drive speed reducer, and the kneading section is provided downstream of the kneading section. A segment type screw having a pressure adjusting portion consisting of a reverse screw or ring plate in which the screw and flight twist directions are opposite to each other, and a concave ring whose cylinder inner diameter is larger than the other sections at positions corresponding to the same pressure adjusting portion of the screw. And a means for solving the problem.

(Function) Behind the raw material supply port, the cylinder can be set to any position in the axial direction by the rotation of the screw provided on the outer surface of the cylinder and the nut whose position is fixed in the axial direction with respect to the reducer. Combining a screw with a pressure resistance part such as a flight with a reverse twist and a cylinder with a pressure relief part with a partially enlarged inner diameter, the screw internal pressure, that is, the kneading characteristics, is optimally selected by adjusting the position of the cylinder that moves in the axial direction to enable.

(Embodiment) The present invention will be described below with reference to the embodiment of the drawings.
The figure shows a side sectional view of a cylinder moving device of a twin-screw extruder showing an embodiment of the present invention. In the figure, reference numeral 111 denotes a reduction frame and a fixed frame of a twin-screw extruder (not shown). Reference numeral 113 denotes an adjustment nut which is in contact with the fixed frame 111 on the rotating sliding surface 116, and is rotatable by inserting a bar (not shown) into the hole 113a. 112 is a holding plate (fixed to the fixed frame 111 with bolts, etc.)
It is restricted from moving in the axial direction. Reference numeral 121 denotes a cylinder, which is connected to the adjustment nut 113 with a screw 121a, and
Are fitted on the sliding surface 115 in the axial direction. The tip of the cylinder 121 is supported by a support member 120, and the support member 120 is slidable on the guide surface 119 in the axial direction. Reference numeral 114 denotes a fixed nut, and when the adjustment nut 113 is rotated with the nut loosened, the cylinder 121 moves in the axial direction. Reference numeral 122 denotes a raw material supply port. The screw shaft 106 integrated with the screw 103 is connected to a rotational drive reducer (not shown) so as not to move in the axial direction.

FIG. 2 (a) shows an adjusting section of the screw internal pressure. The screw 101 has an integral structure with the screw 103, and is connected to the screw shaft 106 in a segment manner, and portions indicated by reference numerals 102, 104, and 105 are also connected to the screw 103 in the same manner. Reference numeral 102 denotes a kneading screw having a high kneading function. In this embodiment, five kneading plates 102a are attached with their phases shifted. The screw 101 has a function to reverse the resin.
03 and 104 are opposite in the twist direction of the flight 105. 12
Reference numerals 3 and 124 denote concave cylinders having a larger inner diameter than the cylinder 121, and the resin passage 126 is larger than the normal gap 131. Also the second
FIG. 7A shows a case where the screw 101 is located at the large diameter portion of the concave cylinders 123 and 124, so that the backflow function is weak and the pressure of the kneading screw 102 is low, that is, the kneading function is low. FIG. 3 is a sectional view taken along the line A-A in FIG. 2 (a).

FIG. 4 shows a state in which the rotation of the adjustment nut 113 in FIG. 1 causes the cylinder 121 to advance with respect to the screws 101 to 104, and the screw 101 is combined with a normal cylinder inner diameter portion.
FIG. 5 is a sectional view taken along the line BB of FIG. When the screw 101 is at the position shown in FIG. 4, the gap 131 is small and the backflow function is sufficiently large.
2, the kneading function is enhanced. Further, since the positions of the cylinders 121, 123, 124 with respect to the screws 101 to 104 can be arbitrarily selected, the kneading function of the screws 102, 103 can be easily adjusted.
The screw 103 may be extended in place of the kneading screw 102. In addition, the shape of the pressure adjusting section is not limited to the reverse screw flight shown in FIGS.
A ring-shaped member showing another embodiment shown in FIGS. 7 and 7 may be used.

FIG. 6 shows a ring-type pressure adjusting mechanism, and FIG.
It shows CC sectional drawing of the figure. In the figure, 107 and 107 ′ are adjacent to each other by a ring plate, and there is substantially no resin flow in the gap 110, and the resin flows through the gap 131. The pressure for enhancing the kneading function depends on the length L in FIG. That is, it can be set arbitrarily by rotating the adjustment nut 113 in FIG. A kneading screw 102 as shown in FIG. 2A can be combined with the upstream side of the ring plate 107.

(Effects of the Invention) As described in detail above, in the present invention, the cylinder movement adjusting device is provided between the raw material supply unit and the screw drive speed reducer,
Because the cylinder position can be adjusted to move in the axial direction,
The cylinder position can be easily adjusted even while the screw is rotating. Because the cylinder position can be adjusted in this way,
Screw internal pressure, that is, screw kneading characteristics can be selected to an optimum value. Further, since there is no sliding portion and no gap in the pressure increasing portion in the cylinder, it is possible to prevent a disadvantage that the cylinder cannot be moved by the invading resin as in the related art.

Also, the present invention corresponds to a segment type screw having a reverse screw or ring plate in which the screw and the flight of the flight are opposite in the twist direction of the screw of the kneading section and a pressure adjusting section of the same screw downstream of the kneading section. A cylinder having a concave ring with a larger cylinder inner diameter than the other sections is provided at the set position, so that the screw internal pressure, that is, kneading characteristics, can be optimally selected by adjusting the position of the cylinder that moves in the axial direction.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a pressure adjusting device of a twin-screw extruder according to a first embodiment of the present invention, and FIG. 2 (a) is a view of a pressure adjusting portion (at low pressure) located at a front portion of FIG. FIG. 2 (b) is a sectional view taken along the arrow F of FIG. 2 (a), FIG. 3 is a sectional view taken along the line A-A of FIG. 2 (a), FIG. 5 is a sectional side view of a pressure adjusting unit (when high pressure is applied), FIG. 5 is a sectional view taken along line BB of FIG. 4, and FIG. 6 is a pressure adjustment of a twin-screw extruder showing a second embodiment of the present invention. FIG. 7 is a side sectional view of the pressure adjusting unit in the conventional twin-screw extruder, FIG. 7 is a sectional view of FIG. Sectional view, FIG. 10 and FIG.
FIG. 11 is a side sectional view showing a state where the barrel is moved to the right from FIG. 8, FIG. 12 is a sectional view taken along line E-E of FIG. 11, and FIGS. 13 and 14 are other conventional examples. It is a sectional side view which shows the twin-screw extruder. Explanation of main parts in the figure 101, 103, 104… Screw 102… Kneading screw 107… Ring plate 113… Adjustment nut 114… Fixing nut 121… Cylinder 121 a… Screw 122… Material supply port 126… Resin passage

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yukio Goto 1 Nagoya Kikai, Iwazuka-cho, Nakamura-ku, Nagoya City, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. A) JP-A-2-255318 (JP, A) JP-A-60-245537 (JP, A) JP-A-1-289775 (JP, A) JP-A-2-12820 (JP, U) JP-A-62 −33422 (JP, U) Japanese Utility Model 2-114488 (JP, U) Japanese Utility Model 2-54439 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A twin-screw extruder capable of inserting and removing a screw without disassembling a cylinder, comprising: an adjusting nut and a nut which rotate to move the cylinder position in the axial direction but cannot move in the axial direction. A cylinder moving mechanism consisting of a screw part of a cylinder for screwing the screw is provided between the raw material supply part and the screw drive speed reducer, and the screw and flight of the flight of the kneading part are opposite in the reverse direction downstream of the kneading part. A segment-type screw having a pressure adjusting portion composed of a screw screw or a ring plate, and a cylinder having a concave ring whose cylinder inner diameter is larger than other sections is provided at a position corresponding to the same pressure adjusting portion of the screw. Pressure adjusting device for twin screw extruder.